Solve the recurrence relation also please!

Consider the following disk transportation problem: You are given three pegs named A, B and C. On peg A sit n disks in strict decreasing order of size, with the smallest disk on the top and the largest disk on the bottom. You are required to transport the disks from peg A to peg C, while respecting the following rules: (a) In each move, exactly one disk can be moved. (b) No disk may ever be placed on top of a smaller disk. (c) Each move consists of taking the uppermost disk from one of the pegs and placing it on top of another peg i.e., a disk can only be moved if it is the uppermost disk on a peg. Write down a recurrence relation for computing the total number of moves required to transfer the n disks from peg A to peg C. Hint: Do you see why peg B is required